Can a federal court order a prepayment of fees or costs by a person who makes affidavit that he is unable to pay such costs?

A federal court may authorize the commencement or prosecution of any action without prepayment of fees or costs "by a person who makes affidavit that he is unable to pay such costs." 28 U.S.C. 1915(a) (1988). The district court has broad discretion to make a factual inquiry regarding an applicant's claim of indigency and to deny a section 1915 motion when the applicant is unable or unwilling to verify poverty. See United States v. McQuade, 647 F.2d 938, 940 (9th Cir.1981) (per curiam), cert. denied, 455 U.S. 958 (1982).